Locking iPad for updates. change my Apple ID?
How do I lock my iPad so it can update? How do I change my Apple ID?
Question marked as
Locking an iPad is not necessary to update iPadOS. See this, Update your iPhone, iPad, or iPod touch - Apple Support
If you wish to change your Apple ID, see this. Change your Apple ID - Apple Support and this What to do after you change your Apple ID or password - Apple Support. However, understand that if you change your Apple ID, anything that you have purchased with the old one is locked to that Apple ID and it would be needed along with the password to update any apps. Also, it would be needed for Activation Lock as well.